text:
What does rudder input control in normal law in an A320?
I understand form documentation that in normal law, pedal input is not necessary to keep coordinated flight. It is merely said that using the pedals is not necessary. Later in the documentation it is said that the law for the yaw axis is either normal, alternate or direct (depending on the condition). For the normal law, automatic functions are implemented (yaw damping, coordinated flight). What happens when the pilot provides a non-neutral command on the pedals? Such information is well documented for pitch an roll control (command of load factor and roll rate), but not for yaw.
On the A380, the documentation states that, "A pedal deflection results in a proportional sideslip and bank angle". I found no such precision for the A320, but it seems reasonable to assume the pedals command a sideslip angle.
In normal and alternate law on a A320, do the pedals command a sideslip? If not, what do they command?

Comment, not answer - I’m not entirely sure. I think on any Airbus before A380, rudder pedal directly commands rudder surface deflection (i.e. direct law). If you look at front-on views of the aircraft, you‘ll notice A380 and A350 have beta vanes (sideslip sensors) which are a necessity if you wish to implement a sideslip control loop. Earlier Airbus types don’t have that so cannot have a sideslip control law (but what they actually have I‘m not sure, as I said).

@CptReynolds I'm seeing conflicting sources on how beta is sensed on the A320. One source notes that the A320 has AOA3 at an angle from the horizontal plane of the aircraft. Thus by comparing AOA3 versus the other two AOA sensors, which are on the plane, you can get beta. Another paper says beta is from lateral acceleration, i.e. ball in a tube. Note that beta is displayed on the PFD as the split triangle, so there definitely is beta sensing.

@user71659 Isn’t split triangle simply lateral acceleration (ball in tube), which is related but not equal to beta?

@CptReynolds No. From the FCOM: "This trapezoidal index moves beneath the roll index. On ground, it represents the lateral acceleration of the aircraft. In flight, it shows sideslip (as computed by the FAC)."

You are correct. On all Airbus FBW aircraft, the rudder pedals normally control the sideslip angle, beta. See this presentation for a source, slides 3, 5-6.
As a note, on pre-A345/A346 models, the rudder pedals are mechanically connected to the rudder. However, the FBW system adds in an additional input, via the yaw damper servos, to drive the rudder to the position the FBW control loops want.
Additional details can be found in Advances In Aircraft Flight Control, M. B. Tischer, page 90:

Finally, it was decided that the rudder pedals would command a combination of sideslip and roll angle to restore some of the conventional aircraft behavior.

Figure 5 shows that the rudder command is a gain-scheduled proportional control based on sideslip, yaw rate, roll rate, and roll angle. The gain scheduling is based on airspeed and high-lift configuration.

I think your source on slide 3 actually shows that automatic rudder control is for some roll/beta law, but „manual“ (pedal) input is direct rudder input added to the automatic rudder deflection?

@CptReynolds I explained that in my answer. Generally the action of the pedals through the mechanical link will move the rudder to close to the position the FBW control loops want. The FBW system then adds or subtracts the remainder, via the YD servos and a summing mechanism, to get the rudder position that is desired by the beta law. Thus when the FBW system is working, the rudder is under its control, but when the system fails and stops providing inputs, the mechanical link has full control.

sorry, you need to change this answer. While not specifically stated so in the docs, rudder is always in direct on A320:  when flying single engine you constantly need to adjust rudder pedal deflection (and/or rudder trim) for any speed change, or any thrust change. This would not be the case if pedals would command beta angle.

@Radu094 See my references. I stand by this answer. In OEI, the beta command doesn't have enough authority for thrust asymmetry, so the aircraft enters a stable turn.

I have read you references, and appreciate your effort, but the conclusion is incorrect. Rudder is in direct. I am typerated on A320

@Radu094 So you're saying one independent academic and one official Airbus source is wrong? They say the exact same thing. Airlines don't teach pilots how to engineer planes on purpose, to prevent confusion. This is just something that is not taught because it doesn't affect the operation of an aircraft. Again, I stand by my answer. Pilots are not aeronautical engineers.

I’m saying I’ve actually flown the dang thing and had to correct rudder everytime the speed or thrust has changed. But hey.. if you have academic sources .. :-)

@Radu094 Just realized it's clear. According to the cited book, Airbus used proportional control from beta to rudder command, it avoids problems like integrator windup. Because there's no integral term, when a steady rudder command is necessary to establish perfect tracking, as in OEI, a steady-state error will result. Your reported behavior does not contradict the reported design of the system.

The rudder deflection is the result of the sum of 2 inputs: the pedals and the yaw damper.
Turn coordination is controlled by the yaw damper actuator and has no return to the pedals. Therefore during a turn the pedals won’t move.
What happens when the pilot provides a non-neutral command on the pedals?
If the pilot acts on the pedals during a turn, the yaw damper action will automatically be reduced to maintain a correct coordination, until the yaw damper action is cancelled. Beyond that during a turn the yaw damper will not do an opposite correction, i.e. if the pilot action is beyond the required amount for a correct coordination.
During a leveled flight an action on the pedals is similar to an action on the rudder trim.

I fail to see what your answer adds to the existing ones. Please elaborate those points.

@Manu H, to the contrary of what is said in the comments «  The FBW system then adds or subtracts .........., to get the rudder position that is desired by the beta law »,  if this was true, no side slip should occur whatever the rudder position done by the pilots. In the simulator during a turn if you push slightly the rudder during the turn, the turn keeps centered, but beyond a position the excessive input shows on the side slip, thus during a turn the yaw damper actuator adds the missing amount, but if the pedals input is excessive the yaw damper will not subtract the excess.

please made it clear into the answer and not in the comments.


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Are fly-by-wire fighters protected in AoA?
When thinking about fly-by-wire, I always think about civilian aircraft (Dassault Falcon 7X, Airbus A350...) for which protections are implemented to ensure the aircraft stays in its designed flight envelope (load factor limits to avoid overstressing the airframe, AoA limits to avoid stall, bank angle limits to avoid inverted flight...). All these restrictions help maintaining the aircraft in a manageable situation while in flight. Some (e.g. pitch or bank angle limits) are OK for airliners but counterproductive for fighters. Other are clearly applicable to both (e.g. load factor. You don't want to overstress your airframe or risk a G-LOC).
My question concerns AoA protection. For fighters, I imagine this protection can avoid loss of roll control while stalling. Yet, some fighters are able to fly at AoA obviously beyond stall angle (e.g. during a cobra), suggesting this protection is not present.
Do fly-by-wire fighters have an AoA protection? If so does it prevent stall? (I can imagine a protection triggered only if a limit is reached for at least a certain amount of time, or a limit beyond stall angle but not far beyond.) Does it have to be deactivated for manoeuvre such as the cobra (I expect every system to be able to be deactivated on such aircraft)?

This wiki article has some good information: https://en.wikipedia.org/wiki/Supermaneuverability

Brief answer: Yes, but the protection does not always work.
Most modern fighter aircraft have an AoA limiter. That is different from a stall warning – in case of the McDonnell Douglas F-4 the limit was only 23 degree, below the stall limit. The reason for the limit was the loss of directional stability above 23 degree AoA.
In case of the JAS-39 Gripen the limiter worked in a straight pitch-up but when the pilot repeatedly pitched up during a flight display over Stockholm, the dynamic response overpowered the AoA limiter and the aircraft stalled. It fell like a stone into a public park, miraculously without loss of life.
In another accident the JAS-39 FCS software got confused after the controls could not follow the change in angle of attack quickly enough when one aircraft flew through the wake of another, its adversary in an air combat exercise. This caused the safe limit of 20 degree to be exceeded and the aircraft became uncontrollable.

Let's start from the fact that nearly all airplanes have 'AoA protection' in the form of stall warning.
For automatic stall prevention, strictly speaking, one doesn't need FBW: this can be achieved with traditional automatic control means (the infamous MCAS is, in essence, an example of such a system). On the other hand, FBW does not have to have stall protection: it just allows it to be introduced (typically) without adding extra equipment. So, it's hard to answer the question without considering each particular aircraft.
Of those I know, for example, the original MiG-29 didn't have FBW, but had AoA limiter which pushed the stick forward with considerable force depending on the AoA and its rate. Su-27, with its FBW (originally only in the pitch channel), has a somewhat more comprehensive AoA/load limiter, but essentially works the same way, by forcing the stick forward.
Normally, such system would prevent stall; in fact, the limiters are often set with a considerable margin, allowing an 'ordinary' pilot easy safe control. For 'supermanoeuvres' like Cobra, these limiters have to be disabled.
I'm not completely sure how it works on the latest integrated control systems, but I expect the same thing: normally, stall would be prevented, and only in special circumstances higher AoA would be allowed. In a typical fight, the primary danger is to stall (or overload) during a tight turn or loop, and you want protection for such cases.

When asking the question, I was thinking about FBW aircraft in which computer have full authority over primary flight control surfaces. By "protection", I was thinking of computer refusing pilot's input that can lead to AoA greater than a threshold (such as what is implemented in airbuses with alpha prot and alpha max)

Well, here you are, Su-27 is an example of full-authority FBW. It kind of 'refuses' to follow pilot's input, but this is implemented by resisting the pilot. Call it 'Boeing style' if you like, but I guess this is the 'normal' way for fighters (that have force feedback on the stick at all), which expect the pilot to be in control.

I was expecting the aircraft to authoritatively limit the AoA because in tight turns with the adrenaline of a dog fight, a pilot may give input that can overstress the airframe, risk a G-loc, and a stall.

@ManuH, yes, apparently pilots of the early F-16s, in the heat of a (simulated) dog fight regularly gave input that bent the side-stick, but the aircraft would not stall, so it clearly has AoA limiter. In those early F-16s, the side-stick did not move at all, only registered force, so the pilot didn't know whether they are at the backstop already. That's why a bit of movement was added to provide that information.

@Zeus, an Airbus-style FBW (first appearing in F-16) does have force feedback, because the force on the side-stick corresponds to the desired pitching or rolling moment, which is proportional to the aerodynamic force produced by the control surface. What it does not have is position feedback (except in direct law). In contrast hydraulic control always have position feedback, but depending on the type of power-drive the force may be just crudely approximated to increase with speed (e.g. 737).

Every fly-by-wire type has protective measures to keep it within the designated flight envelope. In the case of agile fighters capable of the Cobra and suchlike, they are designed to maintain predictable airflow at extreme angles of attack, long after the conventional flow over the wing has broken away. Typically this will involve vortex lift at intermediate angles, while at extremely steep angles the forward airspeed (i.e. in the direction of the pilot's feet) will be severely limited by the drag of the wing planform and various techniques may be employed to maintain controllability. Their flight envelope is thus vastly expanded and needs not so much AoA protection as AoA facilitation.

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What airspace are ultralight pilots allowed to use?
So I've been watching videos and thinking about getting into ultra-light aviation. Flying in a personal air-trike or paramotor looks like a lot of fun. Being new to the aviation arena I had a couple questions:

How do the airspace restrictions work?
Do you have to file a flight plan like any typical aircraft/pilot at an airport?

For example, say I wanted to take my paramotor to a large park and take off from there? How would that work with the FAA, talking to ATC and other traffic in the area so they know I'm there? Does it work the same as flying in a Cessna?

I edited your question to clarify some terminology. An ultralight isn't the same as a light sport aircraft, and they operate under very different regulations. You mentioned paramotors and trikes so I assume you're asking about ultralights but please roll back or edit again if I got that wrong.

@fooot I'm not sure what lighting has to do with this question?

@fooot Not a dupe. That question is about lighting.

@Pondlife the answer there quotes the whole regulation which covers airspace too.

Might be a dupe of This question though

@fooot Maybe, but the question is completely different. I thought we discussed this in meta (?) but IMO it's not ideal to direct someone to a different question that 'just happens' to answer this one.

@fooot That regulation about lighting has only one short sentence about airspace. The answers to the other question are much more specific

Ultralights are regulated under 14 CFR 103. There are very few regulations that apply to them, but there are specific rules on airspace in 103.17:

§103.17   Operations in certain airspace.
No person may operate an ultralight vehicle within Class A, Class B,
  Class C, or Class D airspace or within the lateral boundaries of the
  surface area of Class E airspace designated for an airport unless that
  person has prior authorization from the ATC facility having
  jurisdiction over that airspace.

That means, you can fly in (most) class E airspace and all class G airspace. You can find more information about those airspace classes in this question.
As for your other questions:

A flight plan isn't required even for aircraft, and ultralights aren't subject to the regulations that would require them anyway
Ultralights aren't required to have radios or talk to anyone; you usually fly so low that you aren't in anyone's way
It's not at all the same as flying a Cessna; in fact, you don't even need a pilot's license to fly an ultralight
See this question for information about launching from national parks; state parks would be subject to state law instead but the principles are probably the same

You might want to look through all our ultralight questions for more information.

Thank you, Pondlife. Like I said, I'm very new to this area. I've flown commercially plenty of times, and mess around on a flight sim at home; but am just now getting interested in personal flight of the ultralight variety.

I would also suggest finding a local EAA chapter at www.eaa.org

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What is the difference between a rating and a certificate?
I did some research on what it would take to become a private pilot. I am totally green to the aviation world, so bear with me on my question.
I see the licenses also referred to as certificates but I also see the term "rating" listed on many things like "twin-engine", "turbo-prop", etc.
So what is a "rating" vs a "certificate"? Am I over-thinking this?
I'm referring to US regulations.

Can we assume that you're asking about the US? This question might be related, but for questions like this we always need to know which country you're asking about.

OOPS!!! My apologies. Yes, US-based regulations.

You are certified as a pilot to fly a certain class of airplanes. Typically, one would start with Airplane, Single Engine, Land. Then you could have more classes of airplanes added with additional training - tail draggers, floatplanes, complex (200 or more  HP, retractable gear, constant speed propeller),  high performance, multi-engine, etc.
Then you add ratings - instrument rating (can fly in clouds), commercial rating (can fly for hire), transport rating (can fly larger things for hire?).
I may be oversimplifying a little. Go find a local airport with a Cessna 172 or a Piper something and get in the air!

Thanks, @CrossRoads. This makes more sense to me. So the certficates are specific to the machine (basically), and the ratings are more for HOW you use the machine (basically)?

Sort of. A-SEL covers a lot of planes both conventional gear (tail dragger) and nosewheel (tricycle), but you need an additional tail-dragger signoff if you didn't get your license/certificate in one. I don't think you need an FAA Knowledge Exam/Practical test for that like you would for Instrument Rating, Commercial Rating, Transport rating; you only need an Instructor to sign off as far as I know. I've only done my Private and Instrument, and that was 20 years ago, so things might have changed.

See this question also, https://aviation.stackexchange.com/questions/43041/what-counts-towards-the-250-hours-required-for-cpl  It explains the Rating/Class for aircraft types better than I did I think.  Copied the gist below, but the formatting was lost:

Sec. 61.5
Certificates and ratings issued under this part.
(b) The following ratings are placed on a pilot certificate (other than student pilot) when an applicant satisfactorily accomplishes the training and certification requirements for the rating sought:
(1) Aircraft category ratings--
(i) Airplane.
(ii) Rotorcraft.
(iii) Glider.
(iv) Lighter-than-air.
(v) Powered-lift.
(vi) Powered parachute.
(vii) Weight-shift-control aircraft.
(2) Airplane class ratings--
(i) Single-engine land.
(ii) Multiengine land.
(iii) Single-engine sea.
(iv) Multiengine sea.

There is no longer a "transport rating". There used to be, you got an ATR (airline transport rating) but that was supplanted by the ATP (airline transport pilot) certificate. But you do need a "type rating" for large aircraft. For example, my ATP certificate has on it a 747 type rating.

I'm guessing for flying the jumbos like that, there are highly specialized schools you must attend? How would one actually be trained to fly one of those? Obviously an airline wouldn't expend the money to allow one of their aircraft to be flown by a student, right?

This answer is largely wrong: tailwheel and complex require endorsements, not ratings; commercial and ATP are certificates, not ratings. Etc.

@CrossRoads is sort of correct, but is off on the details. The comments cover some of it, and I’d like to clarify and add some detail.
For purposes of airmen certification aircraft are divided into Categories and within Categories there are classes.
14 CFR §61.5 Certificates and ratings issued under this part.

(1) Aircraft category ratings—(i) Airplane.(ii) Rotorcraft.(iii)
  Glider.(iv) Lighter-than-air.(v) Powered-lift.(vi) Powered
  parachute.(vii) Weight-shift-control aircraft.
(2) Airplane class ratings—(i) Single-engine land.(ii) Multiengine
  land.(iii) Single-engine sea.(iv) Multiengine sea.(3) Rotorcraft class
  ratings—(i) Helicopter.(ii) Gyroplane.

A typical student pilot will train in an Airplane with a single engine that is equipped with tires—not floats. When pass their checkride they get their certificate with a Private Pilot, Single-Engine Land rating.
Once they have their certificate, they may begin to fly different airplanes that need endorsements in their logbooks. CFR §61.31 covers these. You would need an endorsement in your logbook to act as PIC for an  airplane with over 200 horsepower; a complex airplane—controllable pitch, flaps, and retractable gear; or with a tailwheel.
A pilot may also get additional ratings to fly multi-engine aircraft, seaplanes, etc. Note that ratings require additional training and testing by a DPE while endorsements require training and logbook endorsements by a CFI.
A type rating is required by §61.31  for Large aircraft (I think this means over 12,500 lbs), turbine-powered aircraft, and other aircraft specified by the FAA.
Earlier I mentioned that when you pass your checkride you will have a Private Pilot rating. There are several other ratings that apply to your certificate, starting with your Student Pilot rating.
14 CFR §61.5   Certificates and ratings issued under this part.(a) The following certificates are issued under this part to an applicant who satisfactorily accomplishes the training and certification requirements for the certificate sought:
(1) Pilot certificates—
(i) Student pilot.
(ii) Sport pilot.
(iii) Recreational pilot.
(iv) Private pilot.
(v) Commercial pilot.
(vi) Airline transport pilot.
(2) Flight instructor certificates.
(3) Ground instructor certificates.
Sport pilot and Recreational pilot certificates have some limitations on the type of aircraft you can fly and require logbook endorsements for some privileges (e.g. flying in Class B for recreational pilot).
The instrument rating (§61.65   Instrument rating requirements.) is kind of odd in that it isn’t listed in the types of certificates, but it is an add-on to your pilot certificate. So a commercial pilot usually has an instrument rating and a CFI must have an instrument rating in order to qualify as a CFI.
Completely separate from all of this, aircraft themselves are classified as well.
Certification of Aircraft is covered by PART 23–AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Among other things it sets out the four types of aircraft that are normally flown in Part 91 operations.
14 CFR §23.3 Airplane categories.
(a) The normal category is limited to airplanes that have a seating configuration, excluding pilot seats, of nine or less, a maximum certificated takeoff weight of 12,500 pounds or less, and intended for nonacrobatic operation. Nonacrobatic operation includes:
(1) Any maneuver incident to normal flying;
(2) Stalls (except whip stalls); and
(3) Lazy eights, chandelles, and steep turns, in which the angle of bank is not more than 60 degrees.
(b) The utility category is limited to airplanes that have a seating configuration, excluding pilot seats, of nine or less, a maximum certificated takeoff weight of 12,500 pounds or less, and intended for limited acrobatic operation. Airplanes certificated in the utility category may be used in any of the operations covered under paragraph (a) of this section and in limited acrobatic operations. Limited acrobatic operation includes:
(1) Spins (if approved for the particular type of airplane); and
(2) Lazy eights, chandelles, and steep turns, or similar maneuvers, in which the angle of bank is more than 60 degrees but not more than 90 degrees.
(c) The acrobatic category is limited to airplanes that have a seating configuration, excluding pilot seats, of nine or less, a maximum certificated takeoff weight of 12,500 pounds or less, and intended for use without restrictions, other than those shown to be necessary as a result of required flight tests.
(d) The commuter category is limited to propeller-driven, multiengine airplanes that have a seating configuration, excluding pilot seats, of 19 or less, and a maximum certificated takeoff weight of 19,000 pounds or less. The commuter category operation is limited to any maneuver incident to normal flying, stalls (except whip stalls), and steep turns, in which the angle of bank is not more than 60 degrees.
(e) Except for commuter category, airplanes may be type certificated in more than one category if the requirements of each requested category are met.

Sport and recreational are certificates, not ratings. And your definition of large aircraft is correct, but if you're looking for the source it's in 14 CFR 1.1.

@Pondlife Thanks, fixed it.

You may want to replace "CFR" with "14 CFR" in your citations, which I assume is the title of the CFR that you're referencing. The CFR has lots of titles, but 14 is the one that contains the federal aviation regulations.

@reirab Fixed it.

There's a lot of detail and even some inconsistencies in these terms but a useful and mostly accurate starting point is:
Certificates define the privileges you have as a pilot; ratings define the aircraft you can exercise (use) those privileges in.

There are several types of certificate, including student, private, commercial, airline transport and flight instructor. Each one has a different set of privileges (permissions) that the pilot has. See 14 CFR 61.5 for the full list.
For example, a commercial certificate gives you the privilege of acting as pilot in command of an aircraft "for compensation or hire", i.e. you can be paid to fly (61.133). A private certificate holder doesn't have that privilege (61.113).
But, that doesn't mean that you can fly just any aircraft for compensation or hire; you need a rating for the aircraft first. A rating is required for a general category (e.g. airplane) plus class (e.g. single-engine land or single-engine sea) of aircraft. A type rating is required for a large aircraft, a turbojet airplane, or any other aircraft that the FAA decides should require one (61.31).
That means, if you hold a commercial certificate with "airplane single-engine land" (ASEL) rating, that does not automatically mean you have commercial privileges for "airplane single-engine sea" (ASES). You can certainly add commercial ASES privileges by taking the necessary checkride and getting that additional rating, but the certificate by itself doesn't grant them.
A full list of certificates, categories and classes is in 14 CFR 61.5, and you can find the list of aircraft that require a type rating here.
Unfortunately, there are some exceptions and odd cases that can confuse things. Here are some, I may have missed others:

An instrument rating applies (roughly) to the aircraft category, not class or type (61.65)
A student certificate can be used for training in any aircraft, but before soloing you need training in the appropriate "make and model" (61.87)
You need an endorsement to fly aircraft with certain features - like a tailwheel, for example - but that isn't the same thing as a rating (61.31)
You can have different levels of privileges in different aircraft, e.g. you can hold a commercial certificate with airplane single-engine land rating, but at the same time have private privileges in airplane single-engine sea

That might all seem very complicated but for most students it's actually very simple: you start out with a student certificate and when you pass your checkride you get a private certificate with a rating for whatever aircraft type you learned to fly in, often airplane single-engine land. After that, you can add more ratings, type ratings and/or endorsements, depending on where your flying career takes you.
The bottom line is that you don't need to know this stuff in detail in order to learn to fly, and your instructor will tell you what you do need to know anyway. So don't let the details or regulations put you off flying, just go and do it and you'll learn what you need to know along the way.

Endorsement, that's what I was missing.  That makes it a lot clearer, vs  using rating twice.


text:
Where can I find more details about how ornithopters work?
I learnt about the special helicopter-ornithopter which was put forward by Delft University. Its principle is different from a common helicopter and it doesn't need a tail rotor. But there is very little information about it on the Internet. I sincerely hope that someone can give more details about it, or tell me where to find them.
It operates like this:

What details do you want? At present this question potentially suffers from being "Too broad".

In my answer here you can find more information, and also a link to a thesis about the topic.

I edited your question a little but I'm not sure if you're asking about ornithopters in general, or the Delft one specifically? Also, I don't know what you meant by "scull". I guessed you mean "tail rotor" but I may be completely wrong so please edit again to correct it if you want.


text:
Is precipitation static a concern for small drones?
I read a bit about Precipitation Static buildup on the outside of aircraft flying through dust, rain, or snow.  Can this also happen on a small drone and if so, could it interfere with controlling it?
The FAA has a question on their drone certification test that addresses this and I'm curious if a small/medium size drone would be affected by this.

"The FAA has a question on their drone certification test that addresses this": I never noticed any certification test for sUAS aircraft on their site. What exactly are you referring to?

Also, related Q/A

Fly under the FAA's Small UAS Rule
(Part 107): https://www.faa.gov/uas/getting_started/

Static electricity buildup could affect communications. Static wicks on trailing edges of flaps, ailerons, rudder, elevator dissipate the static electricity.  I would imagine drones could be mostly fiberglass construction, so some additional details need to go into construction to provide a path for the electricity to flow, vs an all metal craft where the outer skin can be that conductor.

This is a good question. I have not found any research on small multirotor drones to indicate that static buildup is an issue that would affect either flight control or telemetry communications with the ground station. I believe this is because of the generally low velocity of the air movement over the components of the multirotor other than the propellers.
Most multirotor drones are built with carbon fiber frames which are typically conductive due to their inclusion of carbon. There would naturally be a need to drain off any static from the frame with a thin metal filament only if that static were found to be an operational issue.

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Can I log flight training outside the US in a US-registered aircraft?
I work outside the USA. I have access to fly an airplane with work. I'm working on my instrument rating. Can the time I'm flying be used towards my instrument rating requirements? We always fly on an IFR flight plan and I can fly "under the hood." The guys that I'm working with are all CFII and willing to sign my log book and the a/c have N tail numbers.

Yes. The FAA doesn't care where you fly, and you can even log training time with a foreign instructor. Logging time in a US aircraft overseas is completely fine.

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Is using a VOR considered IFR or VFR?
As the title mentioned.
And also, is using it in zero visibility (or near) a real life scenario?

You can navigate using VORs under either IFR or VFR. If visibility is zero, hopefully you are flying IFR.
These days, pilots are going to use GPS if at all possible, but if the GPS fails or if the plane doesn’t have GPS, we can fall back to using VORs. Most planes still have one or two VOR receivers for that purpose, even if they’re rarely used.

And of course most GA planes were built before there was a GPS, and the VOR is typically integrated into the COM radio, so it would be a major expense to remove & replace them.

@jamesqf - What percentage of GA aircraft flying today don’t have at least one GPS unit. In my area, it is not very many in the rental and flying club fleets at least. Replacing at least one of the radios with a G430 or G530 is quite common. Or, at least adding a Stand alone GPS unit built in to the panel in addition to the 2 original NavCom radios. After all, those old NavComs end up being replaced just due to the cost to repair them when they break. Systems like the G430 will have Comms, VOR, ILS, & GPS all built into the one unit.

@Dean F.: I wouldn't know the percentage, nor have I had anything to do with rentals since maybe the mid-1980s.  However, I wouldn't consider rental/club planes typical, since they're used for instruction, and these days you probably need a GPS unit for instrument instruction, if not basic.  (So your customers wind up paying :-))  But for us ordinary folks who basically fly VFR, why would we pay $5K, plus (per a quick Google) several thousand more for installation?

No, the use of a VOR is not considered flying IFR. Although you can fly IFR using a VOR for navigation. You can also fly VFR using a VOR for navigation. Radio equipment other than VOR can also be used for navigation in both IFR and VFR flight. And, flying IFR in zero visibility is a real life scenario. But, you can not use a VOR by itself to land in zero visibility.
You can fly both IFR and VFR without using a VOR or even having one installed/operational in the aircraft (depending on aircraft certification). Though, if a VOR is used for navigation, it must have been inspected as functional and accurate by a certificated pilot within the preceding 30 days of the flight for which it is being used.
IFR (Instrument Flying Rules) is a set of rules, procedures, and regulations governing the flight of aircraft solely with reference to flight instruments instead of the ground. You can fly IFR in IMC (Instrument Meteorological Conditions) or in VMC (Visual Meteorological Conditions).
IMC would preclude referencing the horizon. But, it would not necessarily mean that you have zero visibility. You can not fly VFR in IMC unless you remain in sufficient visual conditions to maintain specific distances from clouds and specific visibility.
These rules include requirements for specific equipment for the aircraft and training for the pilot. Navigation equipment is included on the list of equipment. Although a VOR can be used to satisfy the navigation equipment requirements, a VOR is not specifically required. GPS is a suitable radio receiver which can be used for both IFR and VFR operations instead of or in addition to VOR. In some areas of the world, an NBD/ADF receiver would suffice. In the past other systems like LORAN would have been included in the list of suitable radio navigation equipment.
Think of it this way. Flying IFR means to fly by flight instruments only. A VOR receiver and indicator are not flight instruments. They are navigation instruments. The only navigation instrument that is specifically required by regulations for IFR flight is a DME (or DME equivalent like a GPS) above Flight Level 240. Otherwise navigation equipment is included in the requirement for radios pertinent to route of flight. Radios pertinent to flight is already required in the stipulation to maintain two-way radio communication with ATC.
Title 14 of the Code of Federal Regulations Part 91.205

(d) Instrument flight rules. For IFR flight, the following instruments and equipment are required:
(1) Instruments and equipment specified in paragraph (b) of this section, and, for night flight, instruments and equipment specified in paragraph (c) of this section.
(2) Two-way radio communication and navigation equipment suitable for the route to be flown.
(3) Gyroscopic rate-of-turn indicator, except on the following aircraft:
(i) Airplanes with a third attitude instrument system usable through flight attitudes of 360 degrees of pitch and roll and installed in accordance with the instrument requirements prescribed in §121.305(j) of this chapter; and
(ii) Rotorcraft with a third attitude instrument system usable through flight attitudes of ±80 degrees of pitch and ±120 degrees of roll and installed in accordance with §29.1303(g) of this chapter.
(4) Slip-skid indicator.
(5) Sensitive altimeter adjustable for barometric pressure.
(6) A clock displaying hours, minutes, and seconds with a sweep-second pointer or digital presentation.
(7) Generator or alternator of adequate capacity.
(8) Gyroscopic pitch and bank indicator (artificial horizon).
(9) Gyroscopic direction indicator (directional gyro or equivalent).
(e) Flight at and above 24,000 feet MSL (FL 240). If VOR navigation equipment is required under paragraph (d)(2) of this section, no person may operate a U.S.-registered civil aircraft within the 50 states and the District of Columbia at or above FL 240 unless that aircraft is equipped with approved DME or a suitable RNAV system. When the DME or RNAV system required by this paragraph fails at and above FL 240, the pilot in command of the aircraft must notify ATC immediately, and then may continue operations at and above FL 240 to the next airport of intended landing where repairs or replacement of the equipment can be made.

VFR
VORs are central instruments for both VFR and IFR flying. A VOR is used in VFR flight often to facilitate long distance navigation or find relative position with respect to various VORs/Airports around the aircraft.
For example, an aircraft with a dual VOR system can tune one to Station A, one to Station B, and then take the bearings/headings of the two to interpolate and determine an approximate location (by intersection of the bearings). VORs can be used to plan cross country flights as well, but GPS is becoming more user friendly and accurate.
IFR:
For IFR flight, VORs are often very important as well. Especially in a non-glass (ie G1000) aircraft, VORs are used to describe IFR Low En-Route Airways - the Victor Airways crisscrossing the United States. They are not considered "required" for IFR flight, but most IFR routes can be flown using Victor airways and hence VORs. VOR approaches are now more deprecated but plenty exist - I just did one a few days ago! A VOR approach is like a localizer approach - non precision, with higher minimums. There are technically "no" IFR approaches that allow for "zero-visibility" - every approach in IFR conditions has a minimum as denoted on the approach plate (IAP).
Here is an IAP for a VOR approach: https://resources.globalair.com/dtpp/globalair_00998V27L.PDF
Note the "S-27L" minimum of 520ft MSL and 1 SM visibility (520-1). A VOR approach has higher minimums than the average RNAV, LNAV, or even Localizer approach because it is not considered accurate enough to take an aircraft to 200-400 feet above the ground. An ILS, which is a precision approach, usually has a minimum of 200-300ft.
So in general, there are no approaches allowed at "zero visibility." Some airliners can do a "Cat III ILS" down to much lower minimums than even a standard ILS, but definitely not with a VOR.
I hope this helps! :)


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Are test pilots certified to fly all aircraft types?
I just saw an hour long MIT lecture for no reason and the lecturer said he has flown over 70 kinds of aircraft.
Does that mean a test pilot is certified to fly almost anything?

Welcome to Aviation.SE! I removed the [military] tag since I don't see anything in your question related to military. If you are only interested in military test pilots, please include that in your question and add the tag again. Otherwise, it would also be a good idea to add a country regulations tag (like [easa-regulations] for EU or [faa-regulations] for the US) since rules for test pilots may vary by location.

More like they are certified to fly without model specific certification. And often they are the people to help create certification processes.

I'm wondering if you saw an hour long MIT lecture for no reason, or if the lecturer, for no reason, said he has flown over 70 kinds of aircraft. Also wondering if the lecturer is certified on 70 different aircraft or if he's (known to be) a test pilot for <insert agency>.

Since you didn’t specify a jurisdiction, I’ll answer for the FAA. Others should be similar.
Pilots must be rated for the category, class and (if applicable) type of aircraft. Category is pretty broad, such as “Airplane”. Class is a bit more specific, such as “Multi-Engine Land”. Type is even more specific, such as “Boeing 737”.
A type rating is required for any type that:

has a Maximum Takeoff Weight (MTOW) of 12,500 pounds or greater, or
has one or more turbojet engines, or
has been designated by the FAA.

There is no limit to the number of ratings a pilot can have, aside from the time, money and skill required to pass a checkride for each one. However, type ratings are only available for certified aircraft.
For experimental (non-certified) aircraft, since no type ratings exist, the FAA can issue a Letter Of Authorization (LOA), which waives the type rating requirement for specific pilots in a specific plane for specific purposes, such as flight testing, training or demonstration.

Common sense dictates that there can't be a certification for an airplane that technically doesn't even exist yet, so there must be some other way, and that would be the LOA.

If it doesn’t exist, you obviously can’t fly it anyway. The LOA is needed for the time between when it is built and when it is certified—if ever. Or when you modify a certified aircraft outside of what its type certificate allows, such as testing a new engine.

To be sure I understand, the LOA covers a pilot for a particular aircraft (or series of prototypes of an aircraft), but is not a blanket, "FreeMan is allowed to fly whatever the heck you develop next", correct?

@FreeMan It will be one or more specific tail numbers.

@FreeMan And before you ask, moving an LOA’d tail number to a different plane without telling them is a good way to ensure you’ll never get another LOA again.

Thanks for the clarification, and drat! There goes my dastardly plan! Foiled again...

Since FreeMan took all of the fun loopholes, is it possible to get a LOA waiving certification for a class (or, gulp, category)?

@CortAmmon LOAs exist to cover cases that can’t be solved within the regulations. The only possibility I can think of is the Powered Lift category, for which there are (AFAIK) no civilian aircraft yet. If you built your own, or somehow bought a Harrier, maybe.

@StephenS https://en.wikipedia.org/wiki/AgustaWestland_AW609

@StephenS If you're rated for a specific category, class or type, is that for the rest of your piloting career? Or do you need to renew your ratings every couple of years?

@Nzall In FAA-land, ratings are for life, but you must be “current” to use them. In some other countries, ratings (and even entire licenses) expire and must be renewed.

I worked as a test pilot for my aerospace employer.  I have a small collection of ratings, and for unusual operations, and for experimental equipment operations we use Letters of Authorization (LOA). We are not involved in airframe certification, but have done a few Supplemental Type Certificates (STC). The most common things we have done are modifications using existing aircraft, and modifying them moving them into an experimental airworthiness classification. Most of our work is with different mission specific payloads and sensors.


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Did the F-8 have a stall speed of 1.6x its landing speed?
Wikipedia says that the F-8 was to have

a landing speed of no more than 100 mph (160 km/h)

This web page says that the F-8 did have

Stalling speed 157 mph.

The two don't explicitly discuss exactly the same thing, but I do note that e.g. the quoted cruise speed of 570 mph agrees on both. Unfortunately, neither page seems to specify the actual landing speed of the final aircraft.
From an aerodynamics perspective, this doesn't really make sense to me: it seems awfully difficult, to not say outright impossible, to have a stall speed that is significantly higher than the landing speed. Intuitively, the two should be just about the same, or the landing speed should be higher than the stall speed.

Did the F-8 actually have a stall speed of around 1.6 times its landing speed as suggested?
Is that even possible?
What were the stall and landing speeds of the F-8?

I'm imagining a landing procedure involving approaching the landing strip from below and following a parabolic flight path to get sort of dumped onto the runway. If you're trying this without the flaps, that is xD

The stall speed your source is referring to may be the speed for a clean stall which means with the flaps are in flight position (= 0°).
Flaps on powered planes usually increase lift as well as drag. This means basically that you can fly slower and stall happens at a lower speed.
Here are the speeds from the F-8D flight manual (big pdf):

From the chart, in landing configuration with 19,000 lbs gross weight, the stall speed is ~113 knots.

does ground effect come in to play for landing scenarios? – Owen

Ground effect reduces the touch down speed by reducing the stall speed below the value mentioned in the manuals.
The strength of the ground effect depends on the construction of the plane. Low wing planes have stronger ground effect then high wing planes.
This means that the difference of landing speed and touch down speed is grater for a Low wing plane. On the other  hand the ground effect increases the flare phase of the landing for a   Low wing plane.

For completeness, since 133 kts is ~130 mph and Wiki is saying that the Navy asked for an airplane with a 100 mph stall speed, do you have another page from the manual that gives landing speeds?  Or just a reason why the Navy let up on that criteria?

113kts... which is still 30% over the original vision of a sub 100mph (<87kts) landing speed.  This is also engine-off (idle) stall speed.  A powered stall could be much slower at high AoA but certainly more of a stunt than standard landing procedure.  The same manual gives standard approach as 130KIAS with the nose falling through at 90KIAS on rollout, so the <100mph landing speed was really just an initial concept, not really what ended up being practical.  The flight manual also suggests to go around at >105KIAS with 4000ft runway remaining, so not exactly a short lander...

@Marius Page 130 of the linked flight manual ;)

does ground effect come in to play for landing scenarios?

@Owen updated the answer

@Marius, 133kts is 153mph.

Regarding the points about the possibility of having landing speeds lower than the stall speed, this entirely possible. Aircraft with large flap systems combined with the use of leading edge extensions can result in very large maximum lift coefficients for an aircraft. In some cases the maximum lift coefficient (cl max) in landing configuration can be more than double that of the clean cl. This is because flaps and leading edge extensions increase the camber and in some cases the area of the wing significantly.
Here is an example of a graph showing the effect of different flap types on section lift coefficient:

As to F-8 specifics, others have answered these questions better than I could.

By stall speed I am referring to clean stall speed which is usually the "stall speed listed for an aircraft"

Does the ground effect affect the landing stall speed?

Ground effect would also increase the maximum Cl of the aircraft but ground effect is only considered to act up to 1 and a half wingspans above the ground. I doubt any manufacturer would include ground effect in their calculations of the landing stall speed. The calculations for ground effect are extremely complex and the region of the flight envelope they effect is small. I think if you are relying on ground effect for a nice slow landing you are in trouble, this is just an opinion though.


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In light aircraft, non-instrument flight, apply (nearly) full aft elevator before beginning the takeoff roll or at some predetermined speed?
Consider a small, light, nose wheel tricycle aircraft, something along the lines of a C152 or similar, sitting at the end of the runway ready for takeoff, with no issues and with all pre-takeoff checks completed.
In general, what is the correct procedure for take-off with regards to the elevator and nose wheel?
One instructor I've flown with taught takeoff as apply nearly full aft (nose up) elevator before beginning the takeoff roll. After rotation occurs, accelerate further to and maintain best climb speed, limited by maximum flaps extended speed (which for the particular type I'm flying are identical). This approach has the obvious advantage of getting the nose wheel off the ground as soon as there is sufficient lift for that, and ensures that one can look straight ahead at the runway, not really having to worry about the instruments at all before rotation, but means you need to be careful to not apply too much aft elevator at the moment the nose wheel lifts off the ground (since you don't yet have sufficient speed to actually fly, and by rotating too quickly you'll end up with a tail strike on the runway).
Another instructor, in the exact same aircraft, advocated neutral elevator until around the maximum speed the nose wheel can take, then slight aft elevator to raise the nose wheel, and more aft elevator for lift-off only when approaching speed of best climb. This has the advantage of keeping you near the ground longer during the takeoff roll, but requires keeping pretty close tabs on the instruments (and possibly adjusting from airspeed to ground speed, because the nose wheel is concerned with ground speed which is likely less than the indicated airspeed because the airplane is facing a headwind component). To me, this seems more complex.
Obviously in both cases, after lift-off, the important number becomes the indicated airspeed (a proxy for which can be engine power and airplane pitch), which should be near the speed of best climb to gain altitude as quickly as possible. That's the easy part.
But while the wheels are still on the runway, why would one prefer one style of takeoff over the other? Are there any particular situations in which either is clearly superior to the other, or is it merely a matter of taste?

I won't answer because I'm in no way authoritative, but the first method sounds downright dangerous to me. You're adding drag to the take off run, and effectively rotating early. You're increasing the chances of a tail strike and increasing your take off run. The only time I've seen something like that advocated is on a soft field ake off. That's backed up by my POH that mentions getting weight off the nose as early as possible

Another reason to get the front wheel off the ground is that there are quite a few strips that have a grass runway bisected with a paved runway. Hitting the pavement with the front wheel could damage it (and is quite the jolt with just the back wheels).

"This has the advantage of keeping you near the ground longer during the takeoff roll.." >> Except in a soft-field takeoff, this isn't really an advantage.

"...(and possibly adjusting from airspeed to ground speed, because the nose wheel is concerned with ground speed...)" >> This isn't really something you should be concerned with. If an aircraft isn't capable of supporting its nose wheel on a hard surface, you've got other issues to be concerned with. And if the headwind is strong enough to make a significant impact on your takeoff speed, it's probably not the best weather to be flying in anyway.

@Shawn Head wind never makes an impact on takeoff speed, your takeoff speed is the same regardless of headwind.

Suppose you were drag racing this airplane, entirely on the ground. Would you score better in the quarter mile with elevators neutral or at extreme?  If your ultimate intent is to take off, is there a reason you would want to score worse in the quarter mile?

@RonBeyer Takeoff indicated airspeed is independent of takeoff ground speed (to within whatever wind the aircraft and pilot can handle), but surely the value of (nose)wheel ground speed at rotation, at some indicated airspeed generating sufficient lift, is influenced by the headwind/tailwind component of the present wind? The wings, for lift, are about indicated airspeed, which at a fixed ground speed varies with the wind; but the nose wheel rotates at ground speed pretty much independently of wind. Or am I missing something completely obvious here? (Wouldn't be the first time.)

@MichaelKjörling Right, it affects ground speed, but you aren't looking at ground speed (nor does the POH mention it) when identifying take-off speeds. You can take off with a 0 ground speed and a 70kt head wind if you want. I don't believe the nose wheel rotates (rotate as in aircraft pitch) in respect to ground speed. The speed at which the wheel spins is influenced by wind in that respect, but I don't see the RPM of the wheel has any effect on when the aircraft can lift it into the air.

@RonBeyer Right, I meant "spin" as in "the wheel spins around its axis", not "rotate" as in "rotate the aircraft to increase lift". I agree that the airplane doesn't somehow magically care whether the airflow over the wings is generated by the engine(s) pulling the airplane forward, or the wind blowing in the opposite direction. However, the wheel seems to be exposed to forces (e.g. friction) in relation to the speed at which it spins relative to the ground, not the speed at which the airplane is moving over the ground. I think, though, that we're getting into non-relevant technicalities here.

@RonBeyer Sorry about that. Guess I wasn't clear. An aircraft lifting off the ground has no relation to how fast the wheels are moving across the ground. If you have a 50 knot wind on the ground, you better believe a 152 will leave the ground with a 0 knot ground speed. My point was that if any wind is strong enough to affect the aircraft enough where you are concerned about converting air or ground speed, then you probably don't need to be in that plane that day.

It's a matter of the conditions you are faced with.
The first instructor was teaching you soft/rough field technique, where the focus is getting as much weight off the nosewheel as soon as possible to minimize its rolling drag on a soft surface. Besides the drag on the nosewheel, the thrust line acting above the drag axis of the mains on soft ground tends to drive the nose down, so you need to compensate for that as well. The other thing is having the wings producing partial lift from the nose being high also helps reduce the effect of the soft ground.
You might also use this technique if the surface is firm but has a lot gravel, that can get sucked into the prop, and you want the prop as far away as possible while the airplane is moving slowly.  I'll start a run on firm surface with loose gravel with the nose held high but let it come down a bit as speed is gained and there is less tendency for the prop to pull rocks up into it.
Thing is, you need the nosewheel for steering control until the rudder becomes effective, so you give up a lot of potential directional control with tail down technique early in the takeoff, so you only use it to the extent you need to.  Besides directional control, the nose in the air condition is very draggy and can delay acceleration, actually extending the takeoff run.
There are basically 3 procedures that I follow:

Soft/rough field - tail low all though the take off to keep weight off the nose wheel and as much weight off the mains as possible.  You may use flap in this case when you wouldn't ordinarily for the same reason.  You stay in ground effect to accelerate before climbing.
Firm but short field - tail low late in the takeoff and rotating early so the airplane gets to flying speed already at its takeoff pitch attitude. This is to have the airplane lift off at the earliest possible point and may include use of flaps that aren't normally used.  You stay in ground effect to accelerate before climbing.
Normal takeoff - elevator neutral or only slightly nose up, for best steering control and acceleration until rotation at the normal rotation speed.

Students using different instructors always discover quite a bit of variation in techniques as instructors apply their personal preferences.  A perennial problem in the industry.

It differs not only by instructor, but by aircraft. A C152 may require full aft elevator with its 90hp engine to get the nose up at low speeds, but I tried the same in a 180hp C172 and was dragging the tail tie-down on the runway after about 100 feet (a scary noise for a student to hear by the way). It can also differ by aircraft loading. My C177 with a stabilator instead of elevators will take yet another technique, so I wouldn't be concerned with different instructors/techniques, the pilot needs to learn to adapt.

Yeah I owned a '68 Cardinal many years ago and could drag the tail skid on the ground at any speed above 35 mph (that's when I realized why the 177's tail skid was so chunky).  Probably has the most tail power of any light aircraft.  But all the same, it is a special procedure and I would never take off with the nose way in the air unless it was really necessary because you are giving up directional control, plus a lot of finesse is required once airborne because you are lifting off into ground effect barely above the stall.

Dave's answer is also helpful, but I found this to be a better fit for my question because it actually elaborates some on when one would use either style of take-off, so I'm accepting this.

The simple answer is that the proper procedure is to do what ever the POH says for that specific aircraft.
It sounds like the instructors are teaching you two different types of takeoffs. The first maneuver sounds to me like a soft field takeoff to me (full back elevator and nose wheel up quickly) and I'm seeing 152 checklists that confirm that procedure. The second procedure sounds like a standard takeoff to me. So its not that either procedure is incorrect but it sounds like they may have been incorrectly presented to you.
I would bring it up with your instructor and point to the POH as reference. Its worth asking the first instructor

why are we executing soft field style takeoffs on an a paved strip?

I would also ask instructor two to show you a soft field takeoff and see what he does, he should do something similar to what the first instructor was having you do.

"why are we executing soft field style takeoffs on an a paved strip?" I did a lot of soft-field style on 8500' paved strips before I was allowed on grass, it was the policy of the flight school to have X number of soft-field takeoffs/landings on pavement before they would sign off on grass. Even after that, they would not allow operation from grass fields unless the student (or renter) demonstrated proper technique on that particular field.

@RonBeyer I agree and have also done similar practice my self. I mention it because it appears that the soft field technique is being presented as a regular takeoff to the student in this case.

Well both are correct procedures in their own ways, though the former does help to alleviate loads on the nosewheel during takeoff.  It’s also the preferred technique for soft field takeoffs in a tricycle gear airplane to prevent the nosewheel from catching abruptly in soft or wet grass or other unpaved terrain and to get the airplane airborne as quickly as possible.  Keep in mind that full aft deflection of the elevators during the takeoff roll acts something like a speedbrake, delaying the time until you reach Vr and increasing the takeoff roll, so this would not be recommended for a short field takeoff technique.
I’d say this:  if your flight instructor assigns you to do it a certain way, follow that procedure.  In the eyes of the FAA, he/she is the authority figure in this situation.

The FAA isn't involved.

Rather than just follow that procedure, I think I'd ask for clarification of why it's done that way so that I can better understand the procedure. The POH is more of an authority than the instructor, and applying lots of elevator on takeoff isn't usually the procedure on a normal takeoff. It's not technically incorrect, but I didn't and wouldn't teach it that way. But there may be a specific reason why your CFI wants you to do that at your airport.

You'll have to demonstrate both methods to the [authority of choice] examiner. Practice them until you can do them smoothly. A third method involves keeping the plane moving as you pull onto the runway, to keep the plane from getting bogged down in the terrain, where you also keep the nosewheel as light on the ground as you can.

Who mentioned the FAA? Not me.

If you're going to get your ppl, an FAA DPE will question your techniques when you are examined. I have two sons in flight school. I found CrossRoads comments spot on.

@DougRyan "If you're going to get your ppl, an FAA DPE will question your techniques when you are examined." The FAA is unlikely to be involved outside of the USA. The examiner might still question one's techniques, but there are many examiners not associated with the FAA. Please do not assume that everyone is in the USA.


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Is it possible to get permission to fly in the DCA “no drone” area?
The entire immediate Washington D.C. area is in a “no drone zone”, in a 15 mile radius from DCA.
Are there ways to get an exemption for activities such as film making, property inspections, etc?

Yes. This page comes up on a quick Google search.

Flying an unmanned aircraft within the 15-mile radius inner ring is prohibited without specific FAA authorization.

Experienced Part 107 and public aircraft operators with justification can file your request through the on-line Access Program (AAP) https://waivers.faa.gov


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What kind of aircraft are currently being used by Boulder County to fight wildfires?
I was wondering, what kind of aircraft are currently being used by Boulder County to fight wildfires? For example, see photo attached of a plane dropping flame retardant on a wildfire over Left-Hand Canyon in Boulder, Colorado.

I would appreciate any insight anyone can share on this. Thank you.

More importantly, why is he gear down during the retardant drop?

@FreeMan I'm guessing a sudden unloading and subsequent pull-up maneuver could cause the gear to gravity drop. Might also help avoid overspeeding.

@FreeMan Apparently, it's written into the STC that they need gear down during drops, supposedly to prevent stalling. I didn't look up the STC myself, but here's an article: https://fireaviation.com/2017/09/16/the-faa-requires-ericksons-md-87s-to-drop-retardant-with-landing-gear-down/. I also seem to remember reading in one of the forums that people felt it was a silly requirement.

It's a McDonnell Douglas MD-87, specifically one from Erickson Aero Tanker.

Source: eatanker.com

In addition to the Erickson MD-87, the Avro RJ85 from Neptune Aviation Services is also being used to fight the wildfires west of Denver. They are currently based at Rocky Mountain Municipal Airport.
I caught a photo of one on the ground just a few weeks ago.

It's an MD-87, the shortened version of the MD-80 series. It's not operated by Boulder County, it's operated by Erickson, which also operates a number of S-64 Skycrane helicopters.


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Why does the Tu-134UBL have a sharp/pointed nose cone?
Russian/Soviet aircraft design has always intrigued me, and even more so when coming across this photo of the Tupolev Tu-134UBL with its pointy nosecone.
Having looked up the performance characteristics of the aircraft, it "only" seems to fly at sub to trans-sonic speeds (max. speed 890km/h or Mach 0.72 at sea level).
Based on my limited knowledge reinforced by this great post, it only makes sense to use a pointy nose cone when the aircraft travels at supersonic speeds.
Therefore, would the reason for the nosecone design be for some other function rather than just aerodynamics? Radar?

Related: Is the “glass nose” Tu-134 design for easier conversion to military use?

According to Wikipedia, the UBL variant of the TU-134 was designed/used to train TU-160 crew, and is using its nose-cone.
As to why, I think we can only assume. I think that a fair assumption would be that it contains the radar from the TU-160 (or a stripped-down version of it), and/or so the crew will have a similar visibility as they would on a TU-160.
The overall performance differences between the TU-134 and 160 are too far apart (the -134 being a subsonic airliner and the -160 being a supersonic bomber) for the shape of the nose cone alone to make any sort of a significant difference.


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Was the colliding object in the Guadalajara accident ever identified?
In December, four months ago, a 737 landing in Guadalajara apparently hit an object and damaged its nose. At the time it was suggested that it might have been a small drone.
Has the object been positively identified?

According to Boeing, there was no foreign object involved at all, and the cause of the damage was  an implosion of the radome due to differential pressure, caused by improper installation of a seal:
From AVHerald:

On May 31st 2019 Boeing reported that a visual inspection of the radome did not show any evidence of a hard or soft body impact, no DNA material was found. Boeing concluded: "The review showed that an interface seal was installed around the entire periphery of the radome with no openings. This configuration lacked the approximately 8 inch opening in the seal along the bottom of the radome interface specified in engineering drawings and the Airplane Maintenance Manual (AMM 53-52-00) radome installation task. This opening in the seal is required to allow the radome area to drain and for equalization of pressure changes across the radome during flight. A review by our engineering team concluded that the lack of this gap likely resulted in differential pressure across the radome during descent which may have contributed to an internal collapse of the radome."


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Why is the landing area of an aircraft carrier angled to port side, not starboard?
On a modern aircraft carrier, the landing area is not aligned with the axis of the ship.
Given this part of the ship needs to be asymmetric, why do most (if not all) angled flight decks point to the left side of the ship (and not the right)? Is there any advantage to favor this side?

I think it allows them to launch and land aircraft at the same time. By having them land a different direction than launch (they launch off the front I believe (in line with the ship)) a go around remains possible. I am not 100% sure of this so I will let someone with more knowledge weigh in.

@Dave - That's pretty much it. The angled deck also allows for additional catapults (which, because they cross the landing area, are only used during an emergency "scramble") but this is secondary to maintaining the ability to bolter.

The comments and answers do not answer the question which is "why port?".  The OP knows why it's angled, just not why the superstructure is on the starboard side.

@Simon You are right. I've updated my answer.

I'm guessing here.  For side-by-side multi crew ops, the captain (sitting on the left) has a clear view of the traffic pattern on the approach and for a bolter and also has the LSOs, paddles etc on that side (and it's natural for a clear view to have them on the other side to the island).

Is this question asking why decks are angled to the left, or why superstructures are on the right? While partially related, those are two separate questions and there appears to be confusion about which is the actual question.

Related questions: Why are the numbers 3, 6, 9 right of the 2, 5, 8 on each and every numpad? And why does a clock's hand rotate clockwise?

I wonder when the first answer will relate the sidedness of the carrier with the spinning direction of props in the time when the convention was started. This is the only reason I can think of which would explain the issue - all other apply equally for both sides.

@PeterKämpf It could also just have started out as something that made sense for the particular ships that first had angled decks (which were converted to angled decks, not first built with them), and then been kept that way in later designs because there's no real reason to not do that.

@Peter Kämpf: I think propeller spinning direction is actually the answer. Because of the spinning direction, left turns are generally easier in propeller aircraft; this is ultimately why we have the convention that the pilot-in-command sits in the left seat, and why traffic patterns at uncontrolled airports generally go counterclockwise. The latter convention seems like a plausible reason to put the superstructure on the starboard side, which then leads to the landing area angled towards port.

It seems the best answer today is from Mark. A study was conducted, the results were taken into account for the choice.

Farhan's answer covered why the deck is angled in the first place. As far as why the landing area of the deck points left instead of right, this is for several reasons:

Angling to port makes the most use of the deck area behind the catapults. Angling starboard would require the catapults to be shifted left off the centerline of the carrier (yes, the carrier does have two additional catapults on the port side, but these can't be used while the carrier is retrieving aircraft, which is more often than you'd think as the carrier maintains regular patrols).
Angling the landing strip toward the "island" (conning tower) of the carrier just doesn't sound like a good idea when you say it. That goes double when you realize the carrier is underway while you're trying to land on it, and therefore you have to lead the landing strip a little. If you don't, you'll end up "behind" the ship and the landing strip. With the landing strip angled to port, a plane on a "lagging" approach (lined up "behind" where the carrier's going to be at touchdown) will have a relatively clear path off to port for a wave-off. Angled to starboard, a plane that's "lagging" the carrier would be pointed right at the tower.
It would be possible to mirror the entire deck layout; island to port, landing area angled starboard. The reason the island is on the starboard side is primarily convention; all U.S. Navy aircraft carriers ever built have been either flush-decked or have had the island to the right. That's thus a familiar sight picture for naval pilots across all eras, and easy to train to. A new carrier design doesn't get the luxury of a whole new crew trained an entirely different way; the Navy's been training pilots since 1910, they've been landing planes on boats since 1927, and they'll do it they way they've been doing it for 88 years, thank you very much.
The Imperial Japanese Navy commissioned two carriers, Akagi and Hiryu, with island-left designs, fielded with the idea that the island-left carrier would sail in formation with an island-right carrier in the same flag group, with opposing traffic patterns that didn't conflict. This procedure never materialized in practice; most carrier groups in both Japanese and U.S. fleets ended up with a single carrier due to their high cost and lower total number, a pattern that continues today, and even when two (or more) carriers were close enough to be called part of the same naval group, they typically maintained a wide enough spacing to permit a left-hand pattern for both ships.

I think the third bullet point actually answers the question. The entire answer, though, is well written and informative.

I would generally agree with point number 3, but points 1 and 2 are inaccurate.  The port catapults, known as the waist cats, are used all the time and cat 4 is actually the only cat on centerline in the Nimitz class. Also, the carrier is always underway during launch and recovery.  You also never lead the deck, you should only reference the deck for lineup.  I'm not sure what you mean by a lagging approach, but if you grossly overshoot the centerline during the approach turn you'll get waved off on the starboard side of the ship, the same would hold true if the decks were reversed.

The 3rd point by itself answer the question. But why do the US Navy decide to built the island on the right? Why does this convention still influence the carrier design several decades latter?

Wild guess here, but in an emergency it is probably easier for a pilot to identify a rough approach angle of all carriers are built the same. After all, the ship might have turn round in the time you where away from it.

@ManuH Remember, at no point was there a clean break in carrier design. New designs always enter service alongside existing designs; also, pilots on the new carriers were trained on the old ones. So, keeping consistency with other ships currently in service will mean this sort of decision will last way past when the ships where it was established leave service.

@cpast The biggest point is consistency.  Naval Aviation, as an institution, is generally opposed to change, because consistency breeds perfection.  Every approach, regardless of location, should be flown exactly the same as it would be at the ship, and the ground track should be painstakingly accurate with each pass to breed muscle memory, proper sight picture, and perfection.  We'll keep flying this pattern until the last Aviator gets fired.

Why is the deck of an aircraft carrier angled to the left?  Because the island is on the right.
Why is the island on the right?  Because studies on the HMS Furious showed that pilots tended to turn left during an aborted landing.

Why this answer is not the selected one?? It goes directly to the subject and clarifies that the choice wasn't arbitrary, out of habit only.

This is the correct answer. HMS Hermes was the follow-up carrier to the HMS Furious and the first with an island, and was originally designed with two islands, later revised to one on the starboard side because of the experience with pilots turning left after an aborted landing, and to give increased width to the flight deck. The following is the reference given from the HMS Hermes Wikipedia article, and is a very good book on the subject. Friedman, Norman (1988). British Carrier Aviation: The Evolution of the Ships and Their Aircraft. Annapolis, Maryland: Naval Institute Press

The innovation of the angled flight decks gives several key advantages:
Most notably, it is far safer for carriers to land aircraft on angled decks that point away from the superstructure, ground personal and aircraft parked forward.  This greatly reduces mishaps involving aircraft crashing into people and objects on the deck.  The reason the landing area is canted to the left is because the superstructure is on the right.  For clarification, the superstructure is always on the right.  The carrier landing pattern has remained constant for decades so that every approach to the carrier will remain as constant as possible.
Edit: To take it a step further, when the decision was first made to place the superstructure on the right side it was likely because the carrier pattern was already a left hand pattern.  Its worth noting that the standard traffic pattern is a left pattern as well, and a superstructure on the left side, during a left hand pattern, would partially obscure the landing area from view during the downwind and approach turn.

Wikipedia cites a book from the Naval Institute Press that traces the decision to put the island of HMS Hermes (the first carrier with an island) on the starboard side in part to the fact that pilots already preferred to turn to port on a missed approach.

@cpast well, there you go, naval aviation doesn't like change and the pattern has been the same forever

The answer lies in the same article section you referenced. There are two animations there, on the right.

As you can see in this animation, the longer runway is for landing. If an aircraft could not stop, it needs to take off again. That is the reason aircraft carriers have the landing strip angled so that it will not interfere with aircraft which are about to take off or the parked ones.
Simon clarifies that OP is specifically asking about why landing runways are not pointed towards the right/starboard side.
While the island1 is usually built on the starboard side of the fight deck, the Japanese aircraft carriers Akagi and Hiryū had their islands built on the port side.
The reason might be more of a tradition that reasons behind it. Please note that there very few aircraft carriers in the world, and only a few countries have it. So there is not a big competition or difference of standards in this area.

1: The superstructure of a carrier (such as the bridge, flight control tower) are concentrated in a relatively small area called an island

And if the cable snaps then the plane ends up besides the ship instead of under where it can destroy the propeller (pilot will eject either way)

This doesn't answer the question asked.

Why all the crossed-out text? If it's not supposed to be there, delete it. If it is supposed to be there, let me read it.

@DavidRicherby I think it's better to keep this crossed-out text as some comments refered to it (and it is made to be readable).

@ManuH Comments that refer to deleted parts of an answer should just be flagged as obsolete. Otherwise, things just get too confusing.

@DavidRicherby I think this usage of crossed-out text has already been discussed multiple times on meta.stackexchange.com The good way for Farhan should have been to delete this answer and re answer the question

I found this answer useful as a reminder of the basics of carrier operations, like where the cats are.  And for the fully top-down view making it easier to visualize that a plane has to deal with as they come in to land.

Prop planes used to (and still do today!) drift  to the side opposite to the propeller rotation direction during take-off. And while it's true that the first carriers were flat-decked (no island, no banking) many pilots begin their training with prop planes.And there were some crazy 50's turboprop carrier operated planes like the A-1 in times immemorial when jets were not quite established as the future of sea-borne aviation.
One might be forgiven to assume that the first "island" carrier designs originating back then had something to do with allowing a quick take-off with the rudder straight compensating for the drift by angling the deck. And as the layout was proven and found good...Just my two cents.

Hi and welcome to Aviation.SE! do you have any reference for your assertions?

you have posted no link :/ (also, consider putting any source you might have in your answer, not in a comment)

sorry, I'm new to this...[link] (https://www.youtube.com/watch?v=ur18PF-6hIc) at 17:38 please observe the F6F Hellcat ,although launched on a catapult, still shows heavy left banking (being heavy ,all filled up with ammo and fuel etc while accelerating). Aircraft were launched in waves at the time, and it was not uncommon to have multiple launch and landing events simultaneously. Imagine that of all those aircraft- the ones that took off  were subjected to unintentional heavy left banking, while the ones that landed -with engines close to idle- were not so much.

@Federico OP said drift opposite propeller rotation.  It is more than just an assertion when you state the cause.

@Blam doesn't change the fact that it does not provide any reference.

@Federico So? No other answer has a reference. Does it need a reference to "prop", "drift", and "opposite" to be valid. Your comment has no reference to reference.  Really does it need  reference to basic physics?

Why always the port side?  There's no technical reason so it can only be convention - for example several carriers operating together could steam in the same direction and launch their aircraft in the same direction too.  The aircraft would be on (approximately) parallel paths so would not have to take special action to avoid each other.
It also occurred to me that the bridge would be always on the right/starboard, docking facilities might be arranged to take advantage of this...
HMS Hermes was apparently the first carrier with the "control tower" (Island) to starboard.  This may be the origin of the convention.  The link states that pilots prefer a port turn on an aborted landing...

The technical reason is that the deck is angled away from the superstructure which is always on the right. This greatly reduces mishaps.

But why is the superstructure always on the right?  This is what the original question is all about.  One of the comments by @Simon seems to give the only possible reason so far (it may favour the left-seat pilot)

Another factor:  Consistency.  Pilots might have to land on something other than their home carrier.  Carrier landings are already very exacting flying, learning one pattern is better than learning two.

At this point in time it's because all carriers in commission have their islands to starboard, so all carriers will continue to have their islands to starboard. From a naval engineering standpoint there's no reason to prefer having the island to starboard vs. port, but from a pilot training standpoint it's important to minimize the differences between carriers in order to minimize pilot confusion.


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Can the fluid from one hydraulic circuit go to another one (voluntarily or not) in flight?
Given the following facts for airliners:

Fuel can be transferred in flight from one tank to another
Hydraulic energy can be transferred without fluid transfer from one circuit to another in flight using a PTU
Many hydraulic components are fed by several hydraulic circuits and thus may use fluid from several hydraulic circuits simultaneously

Can hydraulic fluid go from one circuit to another while in flight?

I'm pretty sure the answer is "no" since it would remove the redundancy you get with separate systems. If you could leak between systems this would give you a single point of failure for all the systems.

Those components fed by several hydraulic circuits use several hydraulic cylinders in parallel, each fed independently of the others by its own circuit.

@PeterKämpf I also susect that but I cannot find any evidence. If you have any, please share.

This depends on how the systems are plumbed, and while this is likely an exception, for some airplanes like the EMB-145, the answer is yes.
The EMB-145 has 2 hydraulic systems.  System #1 serviced the outboard brakes and system #2 serviced the inboard brakes and the parking brake.  The parking brake actuated all of the brakes and this let you transfer fluid between the systems through the outboard brakes.  This isn't a normal procedure, but one maintenance would walk you through if you had low fluid in one system and more than you needed in the other to balance the systems if you were out somewhere without the ability to service the hydraulic fluid.
The procedure was either

Depress and hold toe brakes
Set parking brake
Release toe brakes
Release parking brake

or the opposite, depending on which way you wanted to transfer fluid.
This works in flight or on the ground (don't do this in flight lest you get distracted and end up landing with the parking brake set)

That had to be an interesting ride!

I suspect @RonBeyer's comment is right and the fluids cannot mix.
According to the diagram in this answer (explaining the 3 hydraulic systems in an A320) the rudder (for ex.) happens to be fed by the Green, Blue, and Yellow system.
I found this description of the hydraulic system and control of a B737's rudder. They say

The rudder PCU [Power Control Unit] consists of an input
    shaft / crank mechanism, a dual concentric servo valve to
    control porting of the fluid to the rudder actuator, […].
The rudder actuator is a tandem actuator, having
    two internal piston areas for each hydraulic source (A & B).
    The actuator is capable of positioning the rudder panel
    with either one or both main hydraulic sources available,
    […]

emphasis mine
Given that I doubt the fluids can mix.


text:
What kinds of planes can tow banners?
Planes can sometimes be seen towing banners around large cities or events.
What kind of plane is good for this type of flight? With banners they appear to be flying slower than usual. Is this just an illusion?
What are the practical or regulatory requirements that the plane must meet to be capable? I am tagging with FAA but information about other jurisdictions is welcome.

What kind of plane is good for this type of flight?

The cheap kind. Joking aside, the exact airplane to use depends on the size of the banners or billboards you're going to be towing, but generally speaking you want something reasonably rugged, with good slow flight characteristics, sufficient engine power to be able to overcome the added drag from the banner, and, hopefully, some decent fuel consumption.
I'm not entirely kidding about the cheap part though; banner towing is hard on the airplanes and carries a higher-than-average degree of risk, so you do want to stay away from airplanes that will be expensive to fix, if you can help it.
As for specific types, I've seen banners towed with everything from -152s to Grumman Agcats; a large banner tow operation apparently had a Super Cub with an O-540 bolted to it, so you'll see a ton of different things, but tailwheels seem to be the norm, at least in the US, and many outfits will make additional modifications such as removing engine cowlings to help with cooling.

With banners they appear to be flying slower than usual. Is this just an illusion?

No, they are indeed flying slower. First of all, the added drag from the banner slows the airplane down all by itself. Secondly, you're being paid to advertise, so you want to make sure that people can read whatever sign you're towing. You're not flying the ragged edge of the stall (it's dangerous, uneconomical, and unnecessarily hard on the engine), but you're probably going to be flying on the backside of the power curve.

What are the practical or regulatory requirements that the plane must meet to be capable?

In addition to the practical considerations we've talked about above, banner towing operations require a waiver from the FAA. The company has to apply for it and every pilot must be trained in banner tow operations, pass a review from an approved FAA inspector (who will be watching you perform picks and drops from the ground), and be added to the waiver. The aircraft and tow hitch mechanisms also have to be inspected and approved for banner tow operations, and added to the waiver.
Here is the current FAA Banner Tow Information handbook, covering equipment, operations, waiver information, and other assorted miscellaneous if you're curious to learn more.

In general, towing requires an aircraft capable of safe operation at low speeds, e.g. a low stall speed, since the drag of the banner makes it difficult to reach higher speeds. Good low speed handling also makes banner pick-up and drop-off operations safer and easier. You can see the FAA's manual on towing operations here (PDF).
It's not just airplanes that tow banners.  I worked with a helicopter pilot who used to fly "helibanners."  The advantage is that a very large banner can be towed since the helicopter can handle gusts "dragging" the helicopter down to very low flight speeds and the rotor can provide considerable thrust at low speeds.  The new hazard is that the banner and its rigging can get caught in the tail rotor, which would be catastrophic.  This is usually dealt with by using a special weighted banner design that keeps everything away from the empennage.

Image Source

The helicopter in the image is towing what's known as a billboard. You can't easily see it unless you're up close, but the leading edge of the billboard has a sleeve, inside of which is a fiberglass or carbon fiber pole, (airplane-towed billboard poles will usually have eyelets for the guidelines leading to a ring that the tow rope is attached to - this design looks different though). Not sure if the image captures it or if just a blemish, but the bottom end of the pole has a weight at the end - this ensures that when the billboard is picked up off the ground, it will orient right side up.

Would a helicopter that lacks a conventional tail rotor be better at this? (whether it be a NOTAR, a synchropter, a tandem rotor, or a coaxial rotor)

Generally speaking (I spend a lot of time on the shores of NJ) I see Piper Pawnees, Super Cub's, and a variety of  Citabrias. Here is a good thread discussing it. Keep in mind that a banner creates a lot of drag and will greatly effect a plane that is flying cross wind so power is a concern. Just this past weekend there was a super cub towing a banner over the shore that i was watching pretty closely. They were flying up the shore with almost a 45 degree headwind at about 25Kts (I didn't have the winds aloft on hand that was ground speed). At some points it almost seemed as if he was not moving and at others it seemed as if he was being blown out to sea. It was an interesting real world visualization on the effect of crosswind for sure.


text:
As a student pilot can I fly solo hours from any airport?
I am researching flight school because I am very interested in getting my PPL. I live in DFW I just graduated from college and money is tight. So I am saving money to get the PPL. I know the bulk of the cost is paying someone to train me. My question in regarding the privileges you have as a student pilot.

Actually, the bulk of the cost is renting the airplane.

Your solo flight needs to be endorsed by an instructor. Depending on how far away you go, this could be more than one endorsement needed. You can't go to just any airport. See BoldMethod.com: Basic Solo Endorsements Part 2.

Flying is not the best hobby to take up if money is tight, trust me!

Lol yeah it really sucks that everything is so expensive. Not that a car hobby is any cheaper but if you had to pay 6K just to learn to drive everyone would ride bikes. Barrier of entry is a b*tch.

if you came up with a figure of 6K then there is something wrong with your calculations or you think you will be done in the FAA mandated 40 hours. Most people take 60 hours or more. Also look at this answer for additional costs that you might not have factored in: https://aviation.stackexchange.com/questions/47899/how-much-does-the-faa-private-pilots-license-checkride-cost/47963#47963

No, the airports you can fly from/to must be specifically endorsed by your instructor. Once you have your PPL, you can fly to any airport.

Based on CFI endorsment I can fly solo in the plane specified. So if I show up to an airport with CFI endorsment even if it is a different airport and plane but of the same type. I ask only based on price so if i start at an airport that charges 145 dollars for a cessna 172 but i find another airport that only charges 100 dollars for the same model would i be able to switch?

Also thanks for the quick response

You can switch, but the endorsement for solo is from a specific instructor and they may not (most likely will not) allow you to solo in the new aircraft without some instruction first. Pick your instructor/school carefuly at the start to avoid these types of issues.

Yes, I would suggest researching pricing etc beforehand. Your main goal is to minimize the number of flight hours that is needed before you instructor signs you off for the checkride. Each instructor is different and they all have a different way of teaching/evaluating. If you end of changing instructors miday, you will also end up spending more hours in the flight while the new instructor 'assesses' you

Thanks for all the advice I think I have a lot of research to do.

In addition to the student solo endorsement limiting you to a specific airport (or set of airports), a different flight school or flying club won't let you rent their planes unless you've been checked out by one of their CFIs.  That new CFI will need several hours to check your skills, knowledge, mental state, etc. for themselves before they give you another solo endorsement (and as a byproduct, permission to rent their planes).  It's not quite starting over from scratch, but the additional hours involved can easily negate a small per-hour savings.  If you're even considering that a possibility, then do the research now and just start at the cheaper place, because you're pretty much stuck where you are from the time you solo until your checkride.


text:
Are any of these airline "secrets" true?
I have recently seen a list of things that are not known by passengers of planes. It was found on a site where you have to recheck and double-check everything, but besides obviously wrong facts there are some that I would like to clarify. They are

Often corpse of dead people are transported as the cargo during regular flights.
If the plane lands at night, the lights in the cabin are low, so if the passengers have to evac, their eyes are used to darkness.
The pilots are given different food and must not share it among the crew.
The headphones passengers recieve are in fact used multiple times.

Which of the facts are true?

#2: Why are cabin lights turned off during takeoff/landing?

#3: Is it true that the pilot and copilot are required to eat different meals?

You can see we already have a couple of those addressed on the site. It would be better to ask them separately. The headphones question would probably be better asked on Travel.SE.

@RonBeyer should I delete these parts of the question?

See also here for number 1, and this very interesting answer

This is too broad. The Stack Exchange format just doesn't work when multiple unrelated questions get lumped together.

Examples of #1: UA, DL, AA , List of a bunch of carriers

Downvoted because the claim that these things are "not known".  Now there may be some totally oblivious people who don't realize those are probably commonplace (except #3 - but I'd expect the pilots' union might have something to say about requiring their members to eat standard airline fare :-)), but I'd expect most people would, if they bothered to think about them at all.

what have these (esp. 1 and 4) to do with safety anyway? Unless you're afraid the dead will rise and turn everyone on board into zombies.

Most of these have been answered already, so if you're looking for a brief summary:

"Often" is an overstatement, just sometimes. But dying is part of being human, and not everyone does it within driving distance of their family. Death just means you can't self-load, flying's still on the table.
Yes.
Sometimes. The meals are normal J/F, not anything special though. The answer linked in comments offers the details.
Sometimes. Not the cheap all hard plastic ones.

P.S. Calling this "secrets" that someone "keeps" from anyone is tabloid clickbaiting. You'll find most of them in official documents and on public websites. I suppose "things you never cared to know, so never bothered to ask" wouldn't have grabbed as much attention...


text:
What is in the A320 Smoke and Fume checklist?
What does the "Smoke and Fume Checklist" for the Airbus 320 series look like?
Is it a printed item or is it on the ECAM screen?

Related. The answer is both. Found in QRH and on the ECAM. More from Airbus.

I'm resuming this old question because no answer was given.
It depends on where the smoke is detected (if automatically detected). The following abnormal procedures exist:

SMOKE FWD(AFT) CARGO SMOKE
SMOKE LAVATORY SMOKE
AVIONICS SMOKE
SMOKE/FUMES/AVNCS SMOKE + REMOVAL OF SMOKE/FUMES

The checklists 1, 2, 3 have the corresponding ECAM message automatically triggered when smoke is detected, while the checklist 4 is a long checklist which guides the pilot in identifying the source of the smoke and taking the necessary actions (and has no corresponding ECAM message).
Checklist 1 instructs the pilots to close the air isolation valve and discharge the agent(s).
Checklist 2 instructs the pilots to punch the guy smoking in the toilette contact the cabin crew.
Checklist 3 instructs the pilots to perform the relevant part of Checklist 4.